Add Parts Support to Vandelay Item Import

[Dan Wells]

Modeled after the support added for importing stat cats, let's allow Vandelay to import "parts" data as well. This may be a partial duplicate of bug #1203866.

[Dan Wells (dbw2)]

Branch here:

http://git.evergreen-ils.org/?p=working/Evergreen.git;a=shortlog;h=refs/heads/user/dbwells/lp1548143_vandelay_parts_import

working/user/dbwells/lp1548143_vandelay_parts_import

Basic test plan:
- Configure your item holdings import profile to define a subfield for parts data
- Import a record with a complete item field including a "parts" label in your newly defined subfield
- See that the part data is defined/assigned for the resulting copy/item

[Kathy Lussier (klussier)]

Thank you Dan! You have just made many catalogers in the Evergreen world very happy! I successfully imported records with parts data in a subfield. The parts were assigned to the correct copy and were also available via the bib record's Manage Parts interface.

Merged to master for inclusion in 2.10.